A Maryland woman said Friday that she was sexually assaulted by Virginia Lt. Gov. Justin Fairfax (D) in a “premeditated and aggressive” attack in 2000, while both were undergraduate students at Duke University. She is the second woman this week to accuse him of sexual assault. Fairfax forcefully denied both allegations.

Democratic Party leaders quickly called for Fairfax to resign, including the influential Virginia Legislative Black Caucus. Many who had withheld judgment after the first allegation this week said they could no longer stand by him, including most of Virginia’s Democratic congressional delegation and national Democrats with presidential aspirations.

While Sen. Mark R. Warner (D-Va.) and Rep. Robert C. “Bobby” Scott (D-Va.) said Fairfax should resign if the allegations were true, Sen. Tim Kaine (D-Va.) offered no such equivocation. “The allegations against him detail atrocious crimes, and he can no longer effectively serve the Commonwealth,” Kaine said in a statement. “We cannot ever ignore or tolerate sexual assault.”

Meanwhile, Gov. Ralph Northam (D) told senior staff that he would serve out the remaining three years of his term and would not step down amid his own scandal involving a racist photograph from his 1984 medical school yearbook.

It was a head-spinning turn in a spiraling week of chaos in Virginia. Only a week ago, Fairfax, 39, was preparing to take over as Virginia’s second African American governor when it looked as though Northam, 59, would be forced out over the racial issue.

The new accusation against Fairfax came from Meredith Watson, who said Friday in a statement through her attorney that she shared her account with several classmates and friends immediately after the alleged assault occurred. Watson did not speak publicly Friday, and her lawyer did not make her available for an interview.

“I deny this latest unsubstantiated allegation,” Fairfax responded in a statement. “It is demonstrably false. I have never forced myself on anyone ever.”

Asked what evidence Fairfax had that would demonstrate that the charge was false, spokeswoman Lauren Burke said: “In due time, all the facts will come out.”

Virginia Democrats made clear that their patience had run out, especially after spending the week absorbing one blow after another regarding their top leaders. Besides Northam and Fairfax, state Attorney General Mark R. Herring (D) admitted Wednesday that he wore blackface to imitate a rapper at a college party in 1980.

Democratic U.S. Reps. Gerald E. Connolly, Don Beyer, Elaine Luria, Abigail Spanberger and Jennifer Wexton, in a lengthy joint statement, called for Fairfax to resign. “The past seven days have been some of the most painful we can remember,” they began. Saying that they found Fairfax’s accusers to be credible, the delegation said it was “unacceptable” for Fairfax to continue in office, “particularly in light of Gov. Northam’s situation, which we continue to believe requires his resignation.”

National Democrats piled on, including Sen. Cory Booker (D-N.J.) — who said “it is no longer appropriate for [Fairfax] to serve” — and Sen. Kirsten Gillibrand (D-N.Y.)

Republican leaders in the Virginia state Senate called for criminal investigations while Democrats in the Senate and the House issued a joint statement calling for Fairfax’s resignation.

Duke has asked Fairfax to leave the Sanford School of Public Policy Board of Visitors until the allegations are resolved, officials said.

As the avalanche picked up speed, one state Democratic official said: “I don’t know who has his back.”

Del. Patrick A. Hope (D-Arlington) on Friday night asked Virginia’s legislative services to draft articles of impeachment against Fairfax. Hope said he was uncertain which part of the state’s constitution would apply but added that he hoped he would not have to introduce the measure Monday.

“It’s up to the lieutenant governor to resign before then,” he said.

Loudoun County Board of Supervisors Chairwoman Phyllis Randall, the first African American elected to that position, said in a statement that she could no longer defend Fairfax. “It’s with deep regret and sadness that I have to call for the resignation of Justin Fairfax. . . . I’m heartbroken to have to make this decision.”

Earlier this week, another woman, Vanessa Tyson, accused Fairfax of sexually assaulting her in 2004 while at the Democratic National Convention in Boston. Fairfax also forcefully denied that charge, saying he was the victim of a “smear” and that they had a consensual encounter.

Watson, who came forward Friday, was friends with Fairfax at Duke, but they never dated or had a romantic relationship, Watson’s lawyer, Nancy Erika Smith, said.

“At this time, Ms. Watson is reluctantly coming forward out of a strong sense of civic duty and her belief that those seeking or serving in public office should be of the highest character,” Smith said in the statement. “She has no interest in becoming a media personality or reliving the trauma that has greatly affected her life. Similarly, she is not seeking any financial damages.”

Watson wants Fairfax to resign from office, Smith said.

Fairfax’s statement said he would not step aside. “I demand a full investigation into these unsubstantiated and false allegations,” the statement said. “I will clear my good name and I have nothing to hide. I have passed two full field background checks by the FBI and run for office in two highly contested elections with nothing like this being raised before.”

Smith said the details of Watson’s alleged attack are similar to those described by Tyson, who said that Fairfax had forced her to perform oral sex.

Kaneedreck Adams, 40, who attended Duke with Watson, said that in spring 2000, Watson lived across the hall from her in an on-campus apartment complex and came to her in tears.

“She was upset,” said Adams, a lawyer. “She told me she had been raped, and she named Justin.”

“She said she couldn’t speak, but she was trying to get up and he kept pushing her down,” Adams said. “She said he knew that she didn’t like what was happening, but he kept pushing her down.”

The alleged attack happened at a fraternity house, Adams said.

“We all knew (Fairfax) wanted to be in politics,” Adams said. “He had a reputation for being very friendly. Some of my friends, we called him ‘Sunshine.’ He was a nice, sweet, charming guy.”

Watson’s attorney provided an email exchange from 2016 between Watson and Milagros Joye Brown, another friend from Duke, after Brown invited some Duke friends to a fundraising event for Fairfax’s nascent campaign for lieutenant governor.

“Justin raped me in college and I don’t want to hear anything about him. Please, please, please remove me from any future emails about him please,” Watson wrote on Oct. 26, 2016.

Watson’s lawyer released a second statement after Fairfax’s denial, accusing the him of trying to undermine her credibility. In that statement, the lawyer revealed that Watson had accused a Duke basketball player of rape her sophomore year. The statement said she reported it to a dean at the university, who discouraged her from pursuing it. The basketball player was not named in the statement.

Duke officials said they could not immediately comment.

According to Duke’s alumni directory, Watson majored in psychology and after graduation held jobs in fundraising and grant work for nonprofits and schools, mostly in Maryland.

Carliss Chatman, 39, of Lexington, Va., went to Duke with Fairfax and Watson and said she believes Fairfax did not assault Watson or Tyson.

“He’s a fighter,” said Chatman, who teaches at the law school at Washington and Lee. “When you rise as quickly as he did and go from people having no idea who you are to being the lieutenant governor . . . He expected it; he expected [people] would come out of the woodwork. . . . I think it’s unfortunate that this is the way politics works.”

Chatman last spoke with Fairfax Tuesday or Wednesday, she said. Defending a man accused of sexual assault is not in her nature., she said But “even though I’m a very strong feminist,” she said, “you can take advantage of Me Too and get back at someone you dated. I believe in believing women, but you can’t believe all women because some people lie.”

The allegations hit Richmond at the end of a tumultuous week in which the Democratic Party’s top leaders have been brought low and the future of the executive branch of government appeared in doubt.

Northam was close to resigning Feb. 1 after news of the racist yearbook photo broke. The picture shows one person in blackface and another in Ku Klux Klan robes, and though Northam initially took responsibility for it, he held a televised news conference last Saturday in which he said he was not in the picture.

Though he admitted that he wore blackface to imitate Michael Jackson in a dance contest in 1984, Northam said he would not immediately resign and would seek to clear his name.

This week, as scandals enveloped Fairfax and Herring, Northam resolved to stick it out. On Friday at 4 p.m., shortly after the Fairfax news came out, Northam told his top Cabinet officials that he would serve out his term.

“I went up to him after and let him know that I was going to be supportive of him,” said Finance Secretary Aubrey Layne. “I’m convinced that he does have an understanding of what it’s going to take both personally and politically and governance-wise to move forward. . . . It’s not going to be easy, but I’m going to support him as long as I’m able to do what is right for the Commonwealth of Virginia.”

Fairfax, a former federal prosecutor, has been a rising star in Democratic politics. The great-great-great-grandson of a slave, he is the second African American elected to statewide office in Virginia.

Until this week, Fairfax was perhaps best known for silently protesting the state Senate’s annual tribute to Confederate Gen. Robert E. Lee.

Earlier Friday, Fairfax seemed in good spirits while presiding over the state Senate on the last day of a busy legislative week, including agreement between Democrats and Republican over the state’s budget.

Fairfax strode onto the Senate floor just before 10:30 a.m., shaking hands with staffers and some senators.

Asked how he was feeling, the lieutenant governor responded: “Hanging in; God is good.”